Atypical MRI features in soft-tissue arteriovenous malformation: a novel imaging appearance with radiologic-pathologic correlation

Vascular anomalies: diagnostic features and step-wise approach

The first part of this review article emphasized correct nomenclature, classification systems, and imaging algorithm of vascular anomalies. The second part of the review discusses the individual entities, highlighting the characteristic clinico-radiological features of the commonly encountered ones. A step-wise algorithmic approach is also proposed for the evaluation of a suspected case of vascular anomaly.

Neonatal vascular anomalies manifesting as soft-tissue masses

The broad and heterogeneous spectrum of vascular anomalies ranges from an innocuous localized cutaneous discoloration to complex, extensive and life-threatening diagnoses. While many of these lesions are present at birth, smaller and deeper lesions might be clinically occult for months or years. Certain vascular anomalies commonly manifest in the prenatal or neonatal period and often have suggestive clinical and imaging features that can aid the radiologist in making a correct diagnosis. The characteristics of such lesions presenting very early in life, particularly those manifesting as soft-tissue masses, are the focus of this review.

Vascular anomalies: Classification and management

Vascular anomalies are broadly classified into two major categories: vascular tumors and vascular malformations. Most vascular anomalies are caused by sporadic mosaic gene mutations, and recent genetic studies have advanced our understanding of the molecular pathways involved in their pathogenesis. These findings have suggested new therapeutic approaches to vascular anomalies, focusing on their pathogenetic mechanism. This chapter seeks to integrate an improved molecular understanding within the updated classification system of the International Society for Study of Vascular Anomalies. We emphasize the genetic, radiologic, and interventional aspects of diagnosis and management in hopes of allowing improved multidisciplinary collaboration surrounding these complex and interesting anomalies.

Imaging of Vascular Malformations

Recent advances in imaging have allowed a better understanding of imaging features and classification of vascular anomalies. This article focuses on imaging of vascular malformations; describes the updated classification system and clinical and imaging characteristics of the different subtypes; and discusses the associated syndromes, differential diagnosis, and available treatment options, including the role of imaging in management.

Spectrum of Imaging Manifestations of Vascular Malformations and Tumors Beyond Childhood: What General Radiologists Need to Know

Vascular anomalies encompass a collection of diagnoses that differ greatly in terms of clinical presentation, natural history, imaging findings, and management. The purpose of this article is to review diagnostic imaging findings of vascular malformations and vascular tumors, excluding the central nervous system, that occur beyond childhood. A widely accepted classification system created by the International Society for the Study of Vascular Anomalies provides a framework for this review, focusing on the entities most likely to be encountered by general radiologists, although several rare but clinically important entities are also reviewed.

Role of imaging in the diagnosis of vascular malformations vascular malformations

Imaging evaluation of vascular malformations (VM) is paramount for proper diagnosis and treatment planning. These lesions often present as complex vascular masses with arterial, venous and lymphatic components, requiring the use of advanced imaging modalities for full anatomical characterization. Symptoms also depend of the location and flow characteristic of such lesions and range from: asymptomatic to severe forms of cardiac arteriovenous shunting. We present an overview of the diagnostic work-up of VM per most recent classification systems and describe imaging characteristics of such lesions at ultrasonography (US) and magnetic resonance imaging (MRI) as a diagnostic tool for work-up of such patients.

Clinical and sonographic features of pediatric soft-tissue vascular anomalies part 2: vascular malformations

Vascular malformations are a heterogeneous group of entities, many of which present in the pediatric age group. Sonography plays a major role in the management of children with these vascular anomalies by providing information that helps in diagnosing them, in assessing lesion extent and complications, and in monitoring response to therapy. The interpretation of sonographic findings requires correlation with clinical findings, some of which can be easily obtained at the time of scanning. This has to be combined with the use of appropriate nomenclature and the most updated classification in order to categorize these patients into the appropriate management pathway. Some vascular malformations are part of combined vascular anomalies or are associated with syndromes that include other disorders, frequently limb overgrowth, and these are now being reclassified based on their underlying genetic mutation. Sonography has limitations in the evaluation of some vascular malformations and in these cases MR imaging might be considered the imaging modality of choice, particularly for lesions that are large, that involve multiple compartments or are associated with other soft-tissue and bone abnormalities. In this article, which is part 2 of a two-part series, the authors review the most relevant clinical and sonographic features of arteriovenous, capillary, venous and lymphatic malformations as well as vascular malformations that are part of more complex conditions or associated with syndromes, including Parkes-Weber syndrome, phosphatase and tensin homologue (PTEN) hamartoma tumor syndromes, Klippel-Trénaunay syndrome, CLOVES (congenital lipomatous overgrowth, vascular malformations, epidermal nevi and skeletal anomalies) syndrome, fibro-adipose vascular anomaly and Proteus syndrome.

2014 Revised Classification of Vascular Lesions from the International Society for the Study of Vascular Anomalies: Radiologic-Pathologic Update

Since the publication of the seminal work on the histology-based classification of vascular anomalies by Mulliken and Glowacki in 1982 and the subsequent adoption of an expanded and modified version in 1996 by the International Society for the Study of Vascular Anomalies, an increasing number of vascular lesions have been recognized as histologically distinct entities. Furthermore, there have been significant advances in detailing the behavior and underlying genetics of previously identified lesions. These developments have required restructuring and expansion of the classification scheme so that appropriate therapies may be studied and implemented in affected patients. The new classification retains the broad categories of neoplasms and malformations but now divides the tumor group into benign, locally aggressive or borderline, and malignant, with the malformation group being divided into simple, combined, those of major named vessels, and those associated with other anomalies. Additionally, a category has been created for lesions in which the histology and behavior do not yet allow clear separation into neoplasm or malformation (thus named "provisionally unclassified vascular anomalies"). The known clinical courses and imaging, histologic, and genetic findings of the most common and/or clinically relevant lesions in the newly adopted revised system are reviewed in this article. (©)RSNA, 2016.

Magnetic resonance imaging of pediatric soft-tissue vascular anomalies

Magnetic resonance (MR) imaging can be used in the management of pediatric soft-tissue vascular anomalies for diagnosing and assessing extent of lesions and for evaluating response to therapy. MR imaging studies often involve a combination of T1- and T2-weighted images in addition to MR angiography and fat-suppressed post-contrast sequences. The MR imaging features of these vascular anomalies when combined with clinical findings can aid in diagnosis. In cases of complex vascular malformations and syndromes associated with vascular anomalies, MR imaging can be used to evaluate accompanying soft-tissue and bone anomalies. This article reviews the MR imaging protocols and appearances of the most common pediatric soft-tissue vascular anomalies.